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It was the brightest cosmic explosion ever observed, and astronomers are still hotly debating its origin and implications. But already the giant flare of December 27, 2004, produced by a bizarre star in our own Milky Way galaxy, is providing a partial solution to a 10-year-old astrophysical mystery. Such "magnetar" fla... | <urn:uuid:af6a0353-e4ad-4e53-b7ce-9d917e4ae44e> | 3.59375 | 665 | Truncated | Science & Tech. | 38.888627 |
Two mechanisms for generating rotation in a volcanic plume have been shown. As the plume shoots up at an astounding 200 to 600 meters a second--winds from the environment surrounding the volcano can come into the picture as a horizontal vortex tube that is tilted and stretched as it travels up. This mechanism is simila... | <urn:uuid:1133c0c7-f135-4933-aec0-cefd4da932fb> | 4.0625 | 119 | Knowledge Article | Science & Tech. | 41.94075 |
I am currently taking a biology class. I do not understand this concept. I understand that the electrostatic repulsion of the negative charges, resonance stabilization and hydration stabilization all ...
Warm blooded animals like us keep their temperature constant irrespective of their surroundings. But how do they do ... | <urn:uuid:ab829c47-c717-4f69-83bd-18918e9c26d3> | 3.421875 | 201 | Q&A Forum | Science & Tech. | 52.368441 |
What would it take to go all renewable?
What would it take to use exclusively renewable energy resources? What would you have to add to or take away from your home? How would your life change? For most of my energy entries, I’ve talked about conservation at the individual level. That’s because I know we can make change... | <urn:uuid:11366805-5c15-446f-903b-864bc2f3c3af> | 2.6875 | 871 | Personal Blog | Science & Tech. | 60.014874 |
The “solar weather forecast” for the next few years is for increasingly poor conditions – as the solar cycle picks up, more matter will fly out from the Sun and eventually collide with our planet’s magnetic field, where the trapped high energy particles will then lose energy by radiation, so potentially disrupting many... | <urn:uuid:48d4b635-754f-426f-9a2c-2a4bffec6661> | 3.171875 | 413 | Personal Blog | Science & Tech. | 37.314171 |
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"Flight theory has legs"
I'm not quite convinced. I wonder if Chris examined the hand-claws of
theropods. After all, sinornithosaurs, microraptors and archaeopterygians
had *four* limbs to climb trees with.
"Flight t... | <urn:uuid:8734e78d-fbc9-4f38-8ede-31021182a979> | 3.296875 | 808 | Comment Section | Science & Tech. | 47.268638 |
Alternate name: Lightning Bug
Family: Lampyridae, Fireflies view all from this family
Description Somewhat flattened beetle with threadlike antennae; large, widely separated eyes; and head clearly visible from above. Primarily black, with two bright-red eyespots on its thorax and yellow edging on thorax and wing case. ... | <urn:uuid:7f1a5b8d-7cdf-41bc-b3c6-5ad2e8fb2e0d> | 3.171875 | 277 | Knowledge Article | Science & Tech. | 48.392747 |
Assuming a solid rectangular plate, hinged along one edge. How does one calculate the mass of the plate if the force necessary to lift the opposite edge is known?
This is blatantly a homework question, so we're only allowed to discuss methods, and not give you the answer. With any problem like this the very first thing... | <urn:uuid:fef64026-b316-4202-84a4-f0427385dc19> | 2.84375 | 214 | Q&A Forum | Science & Tech. | 65.776591 |
Thursday, November 20, 2008
Now for a serious post about outer space...
Constellation is the name of NASA's program to return to the moon, and possibly continue on to Mars, or even maybe other destinations in the solar system. It consists of two major components, the Ares booster system and the Orion crew vehicle.
The ... | <urn:uuid:d694384c-e527-4f28-b52e-44c9a20c6f13> | 3.328125 | 2,335 | Personal Blog | Science & Tech. | 35.83971 |
SCons also allows you to identify the output file and input source files using Python keyword arguments. The output file is known as the target, and the source file(s) are known (logically enough) as the source. The Python syntax for this is:
src_files = Split('main.c file1.c file2.c') Program(target = 'program', sourc... | <urn:uuid:15b5733b-4d10-45e1-853f-0ca4ccae1563> | 2.8125 | 180 | Documentation | Software Dev. | 52.651138 |
US, UK and Hong Kong Researchers have produce a unique ‘movie’ of climate reaching back 5 million years, by bringing together data drilled from ocean beds. It reveals three important temperature patterns during the warm early part of the Pliocene period that they couldn’t recreate together in climate models using exist... | <urn:uuid:e4d577a7-a41d-4dc9-a469-69632057e843> | 4.03125 | 329 | Personal Blog | Science & Tech. | 35.331164 |
Orbits 'R' Us!
When we talk about how Earth and the other planets travel around the Sun, we say they orbit the Sun. Likewise, the moon orbits Earth. Many artificial satellites also orbit Earth.
When it comes to satellites, space engineers have different types of orbits to choose from.
Satellites can orbit Earth's equat... | <urn:uuid:be10391b-711c-4d12-bb9c-078fc593a1b0> | 3.859375 | 518 | Knowledge Article | Science & Tech. | 58.173133 |
We have learned two important things from the Berkeley Earth Surface Temperature Study (BEST):
- Denier claims that prior scientific analysis of the key land surface temperature data OVER-estimated the warming trend were not merely wrong, but the reverse was true. Warming has been high and accelerating.
- The Deniers a... | <urn:uuid:eaa45501-c25e-4cb3-a698-4d7a1a672961> | 2.703125 | 1,587 | Personal Blog | Science & Tech. | 55.391253 |
Tuesday 18 June
Elegance coral (Catalaphyllia jardinei)
Elegance coral fact file
- Find out more
- Print factsheet
Elegance coral description
With its distinctive green tentacles, tipped with bright pink, elegance coral (Catalaphyllia jardinei) is one of the most beautiful of all corals. Many individual coral polyps co... | <urn:uuid:d46bdb37-261f-4f27-a7c3-d3707ffb68f3> | 3.09375 | 1,801 | Knowledge Article | Science & Tech. | 31.877323 |
A phylum - also known as a division when referring to plants - is a scientfic way of grouping together related organisms. All the members of a phylum have a common ancestor and anatomical similarities. For instance, all the arthropods have external skeletons. Phlya are large groups and are further subdivided into class... | <urn:uuid:790e61d5-5550-4f50-87aa-640bf546fd25> | 3.671875 | 223 | Knowledge Article | Science & Tech. | 46.405909 |
Chemical rockets operate on essentially the same technology that we've had since the 1930s, and it's dangerous, expensive, and very inefficient. It's high time for a better way of getting to space, and lasers might be the way to do it.
The problem with chemically powered rockets is that they effectively waste a crazy a... | <urn:uuid:2fd7b97f-ae61-4101-9975-c1c12eb5abf8> | 3.53125 | 458 | Personal Blog | Science & Tech. | 49.515909 |
The physics of espionage
As the 23rd Bond movie, Skyfall, hits cinemas, we take a look at the physics behind spying.
Premiering on 26 October, Skyfall, the 23rd film in the official James Bond franchise, sees the reintroduction of MI6’s gadgetmaster, known only as Q. Innovative gizmos have long been a staple of the ser... | <urn:uuid:93430aa0-1200-4037-b399-97bbbac7d02c> | 2.90625 | 1,023 | Knowledge Article | Science & Tech. | 32.463424 |
Today in History – November 28, 1964 – Mariner 4, was launched and became the first successful mission to Mars. Reaching Mars on a flyby on July 14 and 15, 1965, it was the first spacecraft to return close-up images of the surface (center image above) and lasted three years in solar orbit. In Mariner 4′s 21 pictures, t... | <urn:uuid:ef0d8dea-0936-4571-afcb-f58363f68be9> | 4.09375 | 286 | Personal Blog | Science & Tech. | 39.184349 |
With the recent eruption of Eyjafjallajokull added onto the earthquakes in Haiti and Peru its making some scientists wonder if we are experiencing "Tectonic Implosion"
A new study done by the newly created International Panel on Tectonic Implosion (IPTI) reports that there could be a correlation between oil pumped out ... | <urn:uuid:3794162e-96fe-43fa-860a-aac3ea11a79e> | 2.734375 | 368 | Personal Blog | Science & Tech. | 44.427392 |
Biodiversity is the variety of all life on Earth. It includes all the Earth’s habitats and the species that live in them, from the smallest micro-organisms to huge mammals like the blue whale.
Humans depend on biodiversity for food, fuel and other vital services, yet human activity is causing biodiversity to decline. A... | <urn:uuid:b1232666-82ea-4e11-90ce-99ea5bde258a> | 3.9375 | 309 | Knowledge Article | Science & Tech. | 40.597252 |
Data reported by the weather station: 265440
Latitude: 55.86 | Longitude: 26.61 | Altitude: 122
|Main||Year 1975 climate||Select a month|
To calculate annual averages, we analyzed data of 364 days (99.73% of year).
If in the average or annual total of some data is missing information of 10 or more days, this is not dis... | <urn:uuid:24c19f8d-52b4-40b8-b454-e81ab8250ba0> | 2.703125 | 348 | Structured Data | Science & Tech. | 68.873217 |
This is an artist's rendering of solar wind coming towards the Earth and its magnetosphere.
Click on image for full size
is flinging 1 million tons of material out into space every second! We call this material solar wind.
If you add all this material up over the course of a day, it's like the mass of Utah's Great Salt... | <urn:uuid:9a09f6e0-c932-43f9-9b65-8c79d97de165> | 3.515625 | 568 | Content Listing | Science & Tech. | 61.869461 |
.pyofiles so that executing the same file is faster the second time (recompilation from source to byte code can be avoided). This ``intermediate language'' is said to run on a ``virtual machine'' that calls the subroutines corresponding to each bytecode.
int(3.15)converts the floating point number to the integer
3, but... | <urn:uuid:8f0fc7e1-faaa-4477-8199-627d15bf45c6> | 3.046875 | 737 | Documentation | Software Dev. | 60.577372 |
Your worries arise from asymmetry between how you view ordinary mathematics and how you view logic and model theory.
If it is the business of logic and model theory to provide foundations for the rest of mathematics then, of course, logicians and model theorists will not be allowed to use mathematical methods until the... | <urn:uuid:886edcd9-c46e-4b39-bdef-9f44ce8ce939> | 2.84375 | 567 | Q&A Forum | Science & Tech. | 29.247082 |
Genus: Colonies of 4 (or 2, 8, 16) cells attached side by side, arranged linearly or zigzag;
cell body elliptical or spindle or crescent in shape; terminal cells with spiny projections in many species;
cell wall usually smooth, but in some species granulated or dented or ridged
(Illustrations of The Japanese Fresh-wate... | <urn:uuid:32985398-4ac9-4ec1-8e51-498de105750e> | 3.0625 | 185 | Knowledge Article | Science & Tech. | 51.701787 |
According to a new study reported on by National Geographic, all of the flipping, flapping, undulating, kicking, tail whipping, swishing and swoshing that sea creatures use to propel themselves in the ocean may account for a large portion of “ocean mixing” and this in turn may make climate change modeling even more com... | <urn:uuid:871ae520-e400-497f-aad6-65013ef071a3> | 3.609375 | 456 | Personal Blog | Science & Tech. | 46.395179 |
Image 1 in this series (right) was taken from Davis in Feb 1998. The noctilucent cloud is wavy and blueish-white. The picture was taken when the sun was approximately 10 (degrees) below the horizon, but still shining on the noctilucent cloud.
The summer polar mesopause is the coldest region of the Earth's atmosphere, r... | <urn:uuid:d7b1df99-2df4-4c52-94e3-3cd2f31d7ac5> | 3.90625 | 544 | Knowledge Article | Science & Tech. | 27.531909 |
To help study this complex issue, astronomers took a deep
the largest known star forming region in the entire
Milky Way Galaxy.
above recently-released image was taken in 2009 by the orbiting
Spitzer Space Telescope and digitally translated into
colors humans can see,
with the hottest regions colored the most blue.
Vis... | <urn:uuid:9291e2ba-7e37-47f6-bfe5-b2b3bdbc9a87> | 3.6875 | 228 | Knowledge Article | Science & Tech. | 41.714767 |
How many inputs are needed to excite/saturate a neuron
tal at copley.bu.edu
Thu Feb 25 22:47:25 EST 1993
On the one hand, anatomical evidence suggests that a neuron has, on
average, on the order of THOUSANDS of neurons impinging on it. On the
other hand, physiological evidence shows that only a few epsps are
needed to ... | <urn:uuid:3eb9ac11-8742-4719-a507-700568d4bd45> | 2.8125 | 189 | Comment Section | Science & Tech. | 48.215933 |
If we consider the trigonometric form of fourier series, the
fourier series is the summation of a series of of sin and cos
functions that give rise to the given expression.
e.g. y(t)=?(ancos nx +bnsin nx)
summation for n=1 to n=infinity
an refers to a subscript n,
bn refers to b subscript n,
So, the principle of superp... | <urn:uuid:aafd9a4f-3231-4301-a00a-059ccf641a9c> | 3.375 | 172 | Q&A Forum | Science & Tech. | 50.830632 |
||This article needs attention from an expert in statistics. (June 2009)|
Complete spatial randomness (CSR) describes a point process whereby point events occur within a given study area in a completely random fashion. Such a process is often modeled using only one parameter, i.e. the density of points, within the defi... | <urn:uuid:1198896b-2557-483b-af87-18f325d875dd> | 3.46875 | 456 | Knowledge Article | Science & Tech. | 38.27493 |
Cellular Zip Codes: Where's the Postmaster?
In 1970, Nobel laureate Jacques Monod called DNA the "secret of life" and said that the discovery of its structure and function -- especially "the understanding of the random physical basis of mutation" -- means that "the mechanism of Darwinism is at last securely founded" an... | <urn:uuid:ec7109c2-8dad-4b42-b1e0-1574d593bc03> | 3.359375 | 1,059 | Nonfiction Writing | Science & Tech. | 49.563727 |
1. <cell biology> Extracellular material serving a structural role.
2. <plant biology> In plants the primary wall is pectin rich, the secondary wall mostly composed of cellulose.
3. <microbiology> In bacteria, cell wall structure is complex: the walls of gram-positive and gram-negative bacteria are distinctly different... | <urn:uuid:205f5200-2d71-4c05-8372-3c99d13807b5> | 2.828125 | 154 | Structured Data | Science & Tech. | 29.882069 |
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February 1, 2008 Marine biologists, worried that regular harvesting of wild seahorses may threaten the creature with extinction, have begun breeding them in home aquariums. Caring for seahorses requires a three-step water filtration process, three feedings a day, and careful temperature and water chemistry monitoring.
... | <urn:uuid:28717e0a-8d38-4b6c-b4d8-c24662622aa9> | 3.53125 | 495 | Truncated | Science & Tech. | 41.001065 |
August 27, 2012 | 51
Like an adventurer of old, NASA's Curiosity rover is using its spyglass to scope out some as-yet unexplored environs.
The image above comes from Curiosity's 100-millimeter telephoto camera, which, according to NASA, has about three times the resolving power of any previous landscape camera deployed... | <urn:uuid:ebf89e63-e92c-4206-952b-b8419bbdd681> | 3.1875 | 332 | Truncated | Science & Tech. | 34.477169 |
Chapter 8 - Measuring Sustainability
Part 2 - Environmental, Economic, and Social Carrying Capacity
On Earth, without change, we face a future of certainty. That certainty will be that eventually, in the human time scale, we will deplete or irreversibly damage, many of the resources we have come to use for our very sur... | <urn:uuid:3a9a31d9-0958-42a6-a8f9-d9f4737bc48c> | 3 | 426 | Academic Writing | Science & Tech. | 34.745578 |
2012, Week 18
Audio: Part 1 (MP3, 29Mb), Part 2 (MP3, 28Mb)
Dark Mysteries: What is the Universe Made of?
Presenter: Dr. George Djorgovski
MICA Director, Professor of Astronomy and Co-Director of the Center for Advanced Computing Research at Caltech
One of the key goals of the science of cosmology is to determine the m... | <urn:uuid:6df8630d-f93c-4411-befe-897c9c30725d> | 2.859375 | 340 | Audio Transcript | Science & Tech. | 53.0175 |
A Drama of Star Formation and Evolution
The Chandra image of the Tarantula Nebula gives scientists a close-up view of the drama of star formation and evolution. The Tarantula, also known as 30 Doradus, is in one of the most active star-forming regions in our Local Group of galaxies. Massive stars are producing intense ... | <urn:uuid:5729ca37-4765-41d7-a12f-daa6d93e2727> | 3.765625 | 388 | Knowledge Article | Science & Tech. | 44.028462 |
Case Study: Buffering Blood
Cell metabolism is based on the same general principle as the combustion of any fuel, whether it be in the automobile, power plant, or a home furnace. The general combustion reaction is:
CH2O (fuel) + O2 ===> CO2 + HOH
The same reaction occurs in the cells. The "fuel" comes from food in the ... | <urn:uuid:4573d66b-a465-4091-a8c1-1c288586a48d> | 3.828125 | 676 | Academic Writing | Science & Tech. | 62.809438 |
by Eli West
The word “nuclear” means a lot to us today. When we hear it we think of many things: bombs, reactors, uranium, “nuculur,” and radioactive; all of these are connotations of the word nuclear. Let’s explain what each of them means.
We’ll begin with bombs. The common link between nuclear and bombs, is obviously... | <urn:uuid:c13029e7-afa0-44db-a1a9-1e7cb436d632> | 3.546875 | 1,141 | Personal Blog | Science & Tech. | 62.075438 |
3.4 Moment Generating Function
Recall: the moments of a random variable are useful to know, but not so
easy to find.
In cases where we know a formula for the p.d.f., can often find all
moments at once in a convenient way!
Def: Let X be a discrete random variable. Then the
moment generating function of X is the function... | <urn:uuid:09d8ceb0-a099-478e-a60c-802aec1dfc04> | 3.765625 | 1,862 | Academic Writing | Science & Tech. | 79.064093 |
Silly questions about True and False
drs at remove-to-send-mail-ecpsoftware.com
Mon Dec 20 19:12:27 CET 2004
I just upgraded my Python install, and for the first time have True and
False rather than 1 and 0. I was playing around at the command line to test
how they work (for instance, "if 9:" and "if True:" both lead t... | <urn:uuid:9ac7d6dc-3142-40ab-a150-d15c1f317009> | 2.78125 | 259 | Comment Section | Software Dev. | 75.957095 |
In the aftermath of the devastating magnitude-9.0 earthquake and tsunami that struck the Tohoku region of Japan on March 11, attention quickly turned away from a much smaller, but also highly destructive earthquake that struck the city of Christchurch, New Zealand, just a few weeks earlier, on Feb. 22. Both events are ... | <urn:uuid:8a884387-b587-41ea-bee4-644cf9a4e123> | 4.40625 | 1,228 | Nonfiction Writing | Science & Tech. | 33.509974 |
Place four pebbles on the sand in the form of a square. Keep adding
as few pebbles as necessary to double the area. How many extra
pebbles are added each time?
Make a set of numbers that use all the digits from 1 to 9, once and
once only. Add them up. The result is divisible by 9. Add each of
the digits in the new numb... | <urn:uuid:08656bc2-b898-49b0-be74-ce8fd9ec7d71> | 2.6875 | 230 | Tutorial | Science & Tech. | 81.567509 |
Almost anything will become more stiff when you make it cold
enough, no matter how hard it is to start off with. Some things stiffen
quite spectacularly, such as rose petals and racquetballs, since we do
not expect these normally flexible things to become brittle and to
shatter when struck while they are cold.
The word... | <urn:uuid:22c95b41-f938-44e2-814a-2fa0611b6729> | 3.609375 | 634 | Knowledge Article | Science & Tech. | 38.779852 |
One of the true joys of learning about science – as opposed to, say, economics – is that eventually you can usually get to a scientific summary that clears up many of the distortions that popular reports create. In the midst of wading through yet another cherry-picked-evidence blog post (this one on methane) by Andrew ... | <urn:uuid:5b6499f6-fb3c-4fa8-9cc4-57189a8fa8b9> | 3.109375 | 3,309 | Personal Blog | Science & Tech. | 48.385199 |
The high altitude winds which circulate around the South Pole during December and January carry the payload in a broad circle around the vicinity of 77 degrees south latitude. The journey takes about two weeks, and the winds return the payload in the vicinity of McMurdo Station.
The assembled gondola being carried out ... | <urn:uuid:48f356b0-fdf2-4039-b365-31b113bf83e3> | 2.984375 | 1,366 | Knowledge Article | Science & Tech. | 49.816971 |
As the days shorten and the summer sun is slowly setting under the horizon, the frost is returning to the Arctic and American scientists make up the balance of what has turned out to be an unprecedented melting season. The … Continue reading →
Do you recall the big Arctic melting records of 2005 and 2007? Probably you ... | <urn:uuid:9b2ce762-4c78-4c4c-879b-99a31244bca7> | 2.96875 | 401 | Content Listing | Science & Tech. | 29.914455 |
Learn About Electricity
When we turn on a light switch or an appliance, we often don't think about what is happening to bring that electricity to us. Since the early discoveries in the 1800's it has been taken for granted that when you get up in the morning, you will have electricity to run the pump to provide water, l... | <urn:uuid:8b0da8f6-8bff-4fa4-82d8-658b5a57994d> | 3.53125 | 399 | Knowledge Article | Science & Tech. | 41.184942 |
Ant-ferns are intriguing plants that have developed a mutually beneficial relationship with ants, whereby:
Lecanopteris spinosa was discovered by Clive Jermy - Head of the Fern Section at the Natural History Museum for many years - and his colleague Trevor Walker from the University of Newcastle-upon-Tyne during an exp... | <urn:uuid:197d547a-d5c5-4ff5-aa91-b7fa3f275bd1> | 3.09375 | 699 | Knowledge Article | Science & Tech. | 36.466491 |
Research Tools: Simulation
NSSL researchers have created a computer model that can simulate a thunderstorm to study how changes in the environment can affect its behavior. They also contribute to the development of the Weather Research and Forecast (WRF) model used in both research and NWS operations.
The Weather Resea... | <urn:uuid:36a97ecf-0ed3-43b4-8269-71a10676040f> | 3.1875 | 439 | Knowledge Article | Science & Tech. | 21.695543 |
What are sponges?
Calcareous sponge (Leucetta chagosensis) is one of the most common species in tropical Australasia in shaded coral reef habitats. Sponge Clathria craspedia, a unique species found only on the biogeographic transition zone between northern tropical and southern temperate faunas on the east coast of Aus... | <urn:uuid:ee961f8c-0e45-414f-8339-96f1e31ad418> | 4.09375 | 660 | Knowledge Article | Science & Tech. | 31.217421 |
The vorticity advection term is also called the upper level divergence term. The upper levels generally extend from 550 millibars to the tropopause. Upper level divergence occurs when a mass of air is pulled away from a region faster than that mass can be replaced. This most commonly occurs when the upper level wind fi... | <urn:uuid:f4396934-ced1-4b42-8d3b-3aee1a4f1bb2> | 3.875 | 1,008 | Knowledge Article | Science & Tech. | 38.00507 |
This web site is an outgrowth of an agreement between the USGS and the New England Aquarium, designed to summarize and make available results of scientific research. It will also present educational material of interest to wide audiences.
Home page for Coastal and Marine Geology with links to topics of interest (sea le... | <urn:uuid:db2b4d3c-9e5b-4973-8bcc-f5905680e6b5> | 3.015625 | 283 | Content Listing | Science & Tech. | 36.235692 |
Light extinction of particles
Not all particles are the same, many of them have different shape, size, and composition. Some of them reflect or scatter light, and others absorb it. Two instruments on the image, photometer and nephelometer, measure the amount of light absorbed and scattered by particles.
Photometer meas... | <urn:uuid:ccd97ae4-c3c5-4859-9d5d-0af7e38fdd38> | 4.125 | 172 | Knowledge Article | Science & Tech. | 36.348968 |
This article was taken from the August 2012 issue of Wired
magazine. Be the first to read Wired's articles in print before
they're posted online, and get your hands on loads of additional
content by subscribing
Need to perform a lab test in
microgravity? Jeffrey Manber, managing director of NanoRacks, a US company that... | <urn:uuid:e644ef8c-8b57-404a-a88f-f289f8431c69> | 3.1875 | 387 | Tutorial | Science & Tech. | 58.147799 |
Off the Mediterranean coast of Spain, a green sea turtle (Chelonia mydas) gracefully glides over a seagrass bed, chomping a large green bite before the current swiftly takes him to the next patch of grass. Off the coast of Australia, schools of fish weave between the blades, hiding from predators and feeding on algae.
... | <urn:uuid:50df8557-6567-4cc3-a49b-e57e9b2c181c> | 3.390625 | 744 | Personal Blog | Science & Tech. | 41.6488 |
- class Balloon()
that pops up over a widget to provide help. When the user moves the
cursor inside a widget to which a Balloon widget has been bound, a
small pop-up window with a descriptive message will be shown on the
- class ButtonBox()
widget creates a box of buttons, such as is commonly used for
- class ComboBox(... | <urn:uuid:ac9f20cc-8e17-4de9-8f6e-77ca31df57c7> | 2.765625 | 416 | Documentation | Software Dev. | 49.356661 |
McClintock, Peter V. E. (1987) Science of helium in technology. Nature, 326 (6111). p. 340.Full text not available from this repository.
Liquid helium is something of an oddity. Its existence as a liquid at all is rather marginal, as shown by the ease with which it can be vaporized by tiny influxes of heat - just one w... | <urn:uuid:ef900fa8-fe00-4f21-bf70-ee1c861851aa> | 3.078125 | 315 | Academic Writing | Science & Tech. | 53.494066 |
, a: aSa,
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,i W :
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A type of curve with the equation:
x2y + aby - a2x = 0, where ab > 0
This curve was named and studied by Newton in 1701. It is contained in h... | <urn:uuid:c0a7f67e-bdec-4795-8279-1eba42018699> | 2.90625 | 355 | Knowledge Article | Science & Tech. | 82.507837 |
feel that the outflows from these lobes resemble
the exhausts of two jet engines facing each
other nose to nose.
In the adjacent picture, planetary
nebula M2-9 is shown on the left. At right
is a daytime picture of a Delta rocket launched
from Cape Canaveral in Florida with the Stardust
Mission to Comet Wilde in Februa... | <urn:uuid:82858ced-d564-4fad-91cb-6509d607100c> | 2.921875 | 121 | Knowledge Article | Science & Tech. | 46.768714 |
Spike (M.I.) Walker
English photomicrographer Spike (M.I.) Walker has been a consistent winner of the Nikon Small World competition for many years and has published many articles and a book about microscopy. Featured below is a photomicrograph of a freshwater hydra taken with Rheinberg illumination.
Hydras belong to th... | <urn:uuid:eb979f0a-f840-4dab-b447-c9112e51d706> | 3.25 | 425 | Knowledge Article | Science & Tech. | 41.637639 |
The template class is an iterator adaptor that describes a reverse iterator object that behaves like a random-access or bidirectional iterator, only in reverse. It enables the backward traversal of a range.
For a list of all members of this type, see reverse_iterator Members.
Existing Standard Template Library containe... | <urn:uuid:e553365c-2be0-467a-bbb8-f95a9292d2fe> | 3.65625 | 394 | Documentation | Software Dev. | 20.791638 |
How was Uranus discovered?
Why does Uranus spin 'on its side'?
What is responsible for the color of Uranus?
How is the interior of Uranus thought to differ from those of Jupiter and Saturn?
How does the magnetic field of Uranus compare with that of Earth?
Describe a day on Titania.
What is special about Miranda? Explai... | <urn:uuid:27cb4a26-35a5-4f19-b43b-83dad113a8f3> | 4.125 | 147 | Content Listing | Science & Tech. | 57.930624 |
Binary Tree 1.0
Binary Tree can be used to manage an hierarchies of objects within a binary.
Each object of Binary Tree is a node that may have a reference two descendent objects: the right and the left nodes. Each tree node object may contain a data variable of an arbitrary type.
Binary Tree provides functions for add... | <urn:uuid:2cb34ad4-2327-4246-9d9a-0f81bda84be5> | 3.0625 | 138 | Documentation | Software Dev. | 66.792013 |
I wrote a few lines that numerically solve Maxwell's equations.
The result is a moving wave that looks like a single pulse.
This looks strange to me because I expect waves to move in oscillator fashion, perhaps like cos(x).
Why doesn't the wave appear to oscillate?
How does this kind of Gaussian wave work? Can it be br... | <urn:uuid:2476e435-3f16-4735-a33c-69b4bafc7bd0> | 2.796875 | 266 | Q&A Forum | Science & Tech. | 98.482377 |
Earth Day is just around the corner (April 22nd), and I can’t think of a better way to spend it than learning about the “how” behind the natural world. Here are a few good choices for appreciating evolution this Earth Day:
- For All Ages - Ubiquitous: Celebrating Nature’s Survivors by Joyce Sidman – Yes, this is a pict... | <urn:uuid:2ff6e256-cb20-4141-8ab7-50352682bf83> | 2.703125 | 416 | Personal Blog | Science & Tech. | 53.613737 |
By Nick Batson and Tom Johnson
Anyone who’s been keeping up on the news over the past few weeks has undoubtedly heard of the recent discovery by the European Organization for Nuclear Research (CERN) of a subatomic particle that behaves in a manner consistent with how the theorized Higgs boson is said to behave.
The mon... | <urn:uuid:5593215b-de3f-40eb-8370-126781cc87ac> | 3.109375 | 326 | Truncated | Science & Tech. | 38.844971 |
Using NASA's WISE infrared satellite, astronomers estimate there are about 5,000 known meteors that can impact the Earth with sizes of about 100 feet or larger -- that is, larger than the Chelyabinsk meteor. Smaller ones are fainter and thus harder to find.
It makes sense that smaller asteroids pass Earth more frequent... | <urn:uuid:c2a99abd-b996-4b72-919f-9183f15b5b24> | 4.0625 | 732 | Nonfiction Writing | Science & Tech. | 52.105233 |
February 23rd, 2002 12:15 PM
Arrays in C++
In an array, when you allocate the number of arrays,
(ie) int x, y, anarray;
does that make arrays equalling 8 squared as in 64 arrays????
I am not certain how this works so I would appreciate any info people can provide
BTW........ I have found an excellent site for learning ... | <urn:uuid:5fd0f09e-0944-458a-b028-bd7a84d4a696> | 2.859375 | 204 | Comment Section | Software Dev. | 97.155261 |
A well-organized graphical application has three components:
A model is a ``raw'' program module with a programming interface consisting a collection of publicly visible methods or procedures. In Java, the application is typically a single object (containing references to many other objects) and the programming interfa... | <urn:uuid:c586f775-b56d-4a79-9a53-70ccffbc548c> | 3.78125 | 303 | Academic Writing | Software Dev. | 34.105466 |
With Emacs, you can have a drag event without even changing your clothes. A drag event happens every time the user presses a mouse button and then moves the mouse to a different character position before releasing the button. Like all mouse events, drag events are represented in Lisp as lists. The lists record both the... | <urn:uuid:ca0f2883-1d92-4e71-862f-da56c05f5549> | 2.828125 | 299 | Documentation | Software Dev. | 53.151119 |
|Ivars Peterson's MathTrek|
April 24, 2000
Yet these complicated, surprising movements arise from a remarkably simple geometry. A passenger rides in one of seven cars, each mounted near the edge of its own circular platform but free to pivot about the center. The platforms, in turn, move at a constant speed along an un... | <urn:uuid:e046894c-6946-4308-bc40-8351563fb8da> | 3.90625 | 1,367 | Knowledge Article | Science & Tech. | 44.87451 |
Mitochondrial DNA (mtDNA)
is a genome located in the extranuclear mitochondria. mtDNA is inherited
through the maternal egg cytoplasm, with the father's sperm making no
All children of the first
affected woman are affected, including sons. However, only female children can pass the
trait on, again to all of
their desce... | <urn:uuid:305cddb2-68c1-4eba-a1f3-d6acce73ce75> | 3.234375 | 105 | Knowledge Article | Science & Tech. | 44.169 |
Search our database of handpicked sites
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Introduction of the notion
Source: Semantic Aspect Guide; page 24
The class diagram is an indispensable part of object modeling. The diagram is not the model, but a partial, biased illustration of it. Once finished, the class model represents the whole substance of the system, both data and processes. (These two notion... | <urn:uuid:aeb670d7-524e-4866-acd0-3aac4c53b37f> | 3.6875 | 302 | Knowledge Article | Software Dev. | 48.501195 |
Author(s): Keys, P. W., R. J. van der Ent, L. J. Gordon, H. Hoff, R. Nikoli, and H. H. G. Savenije.
In: Biogeosciences 9, 733-746
Type: Journal article
Link to SEI author(s):
Analyzing precipitationsheds to understand the vulnerability of rainfall dependent regions
It is well known that rivers connect upstream and down... | <urn:uuid:beacc08e-06e9-4b91-b590-b5e79ebbd28c> | 2.734375 | 283 | Academic Writing | Science & Tech. | 24.121893 |
Common Name: Millipede (One thousand legs)
Spirobolida Class Diploda
Millipedes are slender, hard-shelled, worm-like arthropods with elongated rounded body segments. The one most commonly seen on the mountain trails and woods is the black and red Narceus annularis, one of about 1,000 North American species.
Potpourri: ... | <urn:uuid:5699c012-ca3b-4b35-85c5-3712e9808bda> | 4.25 | 375 | Knowledge Article | Science & Tech. | 40.449353 |
The San Andreas fault in California is very distinct in the Carrizo Plain east of the city of San Luis Obispo, CA. Many faults can not be seen at the Earth's surface like this.
Click on image for full size
Why Do Earthquakes Happen?
When the giant blocks of rock which, because of plate tectonics, move in different dire... | <urn:uuid:4f9f6a1b-71a0-465f-b243-6d4a5fa9a270> | 3.9375 | 749 | Content Listing | Science & Tech. | 57.207004 |
Logistic Growth This
model illustrates resource-limited population growth. Populations have
a per-capita growth rate and carrying capacity. Two populations
are compared on three graphs: N vs time, dN/dt vs N, and dN/Ndt vs N.
Individuals in the populations are viewed in windows, illustrating that,
even at carrying capa... | <urn:uuid:3ce1ca66-ea45-4026-95df-c63c043b69cc> | 3.375 | 156 | Tutorial | Science & Tech. | 42.961504 |
Asteroids missed us–comets next
By Vernon Whetstone
Did you see asteroid 2012 DA14 last week? I think I did. It was quite a news event.
Combining the very close pass of DA14 with the explosion of a possible asteroid over Siberia injuring more than 1,000 people the day before made for some real headlines.
Even from the ... | <urn:uuid:706d476a-5437-44ff-afec-47f94d8e751c> | 2.96875 | 757 | Nonfiction Writing | Science & Tech. | 57.010841 |
(meteorobs) Question about radiant drift
david at d-entwistle.fsnet.co.uk
Tue Jun 8 05:02:40 EDT 2004
In message <ca18ok+v2c5 at eGroups.com>, bgarcing <bgarcing at yahoo.com>
>What are the factors that affect these? And how to compute these
>factors using elements unique to each stream? Thanks and clear skies.
I don't... | <urn:uuid:100e07dc-4def-485a-adfd-0e0231a68556> | 3.0625 | 529 | Comment Section | Science & Tech. | 60.614042 |
Returns the group number that corresponds to the specified group name.
Assembly: System (in System.dll)
A regular expression pattern may contain either named or numbered capturing groups, which delineate subexpressions within a pattern match. Numbered groups are delimited by the syntax (subexpression) and are assigned ... | <urn:uuid:cc214ff8-85e4-4313-9cc4-7e2fffff9a77> | 2.90625 | 282 | Documentation | Software Dev. | 35.564895 |
Ancient synapsids are interesting for many reasons, but we hope our fieldwork this year in Brazil will help to address a particular problem in synapsid evolution. The oldest synapsids are found in parts of North America and western Europe, and these areas were located in a narrow band near the equator at the time these... | <urn:uuid:ad201cfa-e707-4913-8b07-5614b0d7347b> | 3.640625 | 742 | Personal Blog | Science & Tech. | 22.562702 |
The earliest work in neural computing goes back to the 1940's when McCulloch and Pitts introduced the first neural network computing model. In the 1950's, Rosenblatt's work resulted in a two-layer network, the perceptron, which was capable of learning certain classifications by adjusting connection weights. Although th... | <urn:uuid:ae3ee9a1-ee0e-40bf-b414-1d9763748fb3> | 3.03125 | 176 | Knowledge Article | Science & Tech. | 43.716667 |
Updated on 27 September 2012
Dr Pawan Kumar Dhar, the founding editor-in-chief of Springer's System and Synthetic Biology and director of the Center for Biodesign, Symbiosis, India, is a renowned bio-informatician and systems biologist. Dr Dhar is the inventor of Cellware and is know for artificially making proteins fr... | <urn:uuid:237a5c04-c4ff-4823-adad-b14b9d3949d8> | 2.78125 | 492 | Nonfiction Writing | Science & Tech. | 24.171172 |
rocessing text or long strings in SQL has never been an easy task. SQL is a powerful language for performing fast operations on data sets, but when it comes to processing text or long strings, it's usually reduced to a prosaic procedural language. This article shows a few techniques for facilitating speedy text process... | <urn:uuid:4687e6b2-a353-45ac-ad7b-1ba84c9ba82e> | 2.953125 | 403 | Truncated | Software Dev. | 44.622086 |
Inheritance in Java
Java Tutorial. The extension of Java classes and interfaces 06.fm. Greg Lavender. Slide 3 of 12. 6/15/99. Order of construction under the legacy ….
More PDF Content
Inheritance is a compile-time mechanism in Java that allows you to extend a class (called the base class or superclass) with another cl... | <urn:uuid:5434196a-0fc2-49b0-b539-9a864e5e1acd> | 4.15625 | 283 | Content Listing | Software Dev. | 40.999943 |
Antennae (singular: antenna) in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes.
In arthropods, antennae are connected to the front-most segments. In crustaceans, they are biramou... | <urn:uuid:beee462a-48ea-45d1-bce1-96063e00e4b0> | 3.6875 | 515 | Knowledge Article | Science & Tech. | 39.13335 |
Into the Unknown: Expeditions to Extreme Environments
Jan Rines, Assistant Marine Research Scientist
Graduate School of Oceanography
Jan Rines received a BS in botany from URI and earned an MS and a PhD from GSO. Her research interests include phytoplankton systematics and the biological-physical interactions between p... | <urn:uuid:183b837b-f6a7-480b-9ecb-4055d9d4a901> | 2.8125 | 704 | Nonfiction Writing | Science & Tech. | 33.342024 |
- Why don't birds get electrocuted when they sit on power lines?
- What is electricity?
- How does electricity get from one place to another?
- a closed loop of conductors through which charges can flow
- a substance through which electrical charges can easily flow
- a flow of electrical charges
- a device for producin... | <urn:uuid:3ef00b39-8d7c-4dba-b117-2cce5f452e66> | 3.921875 | 1,235 | Tutorial | Science & Tech. | 56.419202 |
Get fun Tornado Experiments, together with top scoring Chemistry Experiments. These winning Tornado Experiments including Chemistry Experiments are great for all grade levels. We have over 200 top scoring school experiments and science fair projects ready for immediate use for kids of all ages.
Easy Science Fair Projec... | <urn:uuid:9627221d-d69d-4ab5-9a22-ac1ee1ca4de2> | 2.6875 | 769 | Content Listing | Science & Tech. | 29.360183 |
I read a book, years ago, about Java. One of the last chapters was about how to create connections and send/reveice messages between a computer and a server.
Now I need to create a connection between two computers in the same network (peer to peer, or what is it called). The examples in the book used java.net.Multicast... | <urn:uuid:5a7c4a56-6127-4ab7-a456-e0ffe5e6d34a> | 2.953125 | 448 | Comment Section | Software Dev. | 70.59342 |
Matching 2 Tags
Series: Understanding Evolution
This blog series by Dennis Venema undertakes the task of clarifying numerous aspects of evolution that often become misconstrued by Christians. He first discusses the idea of speciation in a population over time, later applying it to the speciation process that occurred a... | <urn:uuid:afeb784f-6d33-48c6-885f-00899b2b2016> | 2.71875 | 561 | Content Listing | Science & Tech. | 29.858623 |
Common optical phenomena are often due to the interaction of light from the sun or moon with the atmosphere, clouds, water, dust, and other particulates. One common example is the rainbow, when light from the sun is reflected and refracted by water droplets. Some, such as the green ray, are so rare they are sometimes t... | <urn:uuid:0fd19910-60ec-490b-b40f-ded8d864998f> | 3.34375 | 1,155 | Knowledge Article | Science & Tech. | 33.855008 |
Also known as Cayley numbers, after their 19th century inventor Arthur Cayley.
Octonions make use of seven unique roots of -1, labelled i0 to i6. Addition and subtraction of them is very straight forward, just as for complex numbers and quaternions. However, multiplication is more complex. In short, each of the followi... | <urn:uuid:0abffb14-aef6-4c59-99fa-ef83f46767de> | 3.265625 | 327 | Knowledge Article | Science & Tech. | 52.031 |
Every year, the government gives scientists money that they use for amazingly cool things, like building robots that dive to extreme underwater depth and record video like this.
Thanks to funding from taxpayers and philanthropists (and, of course the Internets, which come to think of it also launched as a government pr... | <urn:uuid:1e79202d-6655-4852-bd84-e900ddb43c4a> | 2.84375 | 731 | Listicle | Science & Tech. | 46.132991 |
[Tutor] Data frame packages
bjameshunter at gmail.com
Thu Mar 31 20:26:39 CEST 2011
I appreciate all the responses and apologize for not being more detailed. An
R data frame is a tightly grouped array of vectors of the same length. Each
vector is all the same datatype, I believe, but you can read all types of
data into... | <urn:uuid:d1b1cbda-6ce8-4034-9c6d-fb318eb17067> | 2.6875 | 898 | Comment Section | Software Dev. | 65.384056 |
An open topped rectangular box with a square base is to be constructed with a volume of . Find the Dimension that require the lease amount of surface material.
In microcomputers, most of the components are squeezed into a single box-shaped block. If the block has a length equal to twice the width and if the total surfa... | <urn:uuid:9e9de3e2-ec01-4d48-a48b-09277c8fc568> | 3.265625 | 108 | Q&A Forum | Science & Tech. | 53.971053 |